Adebug/Assemble is a pair of Debugger/Assembler for the MC68Xxx family running on Atari and Amiga computers. Years ago commercial product, now GPL.
The Amiga Desktop Replacement
Scalos is a desktop replacement for the Amiga. Some of its features: 100% Workbench replacement, Undo and Redo, 64bit arithmetic, Fully multitasking, Icon imagetypes, Icon datatype system, Icon dragging is more stable, Cybergraphics and Picasso96 24bit color support, Window patterns, Optimised backgroundpatterns routine, Live updating window scrolling, Drawer windows can be iconified, Menu preferences, Application Interface (API)
A fast, unobtrusive and modern cross-platform GUI toolkit. Agar fully exploits hardware acceleration where available, but also supports simple frame-buffer interfaces. Agar is stand-alone and easily portable to new platforms and graphics systems.
AmIDE - Amiga Integrated Development Environment is a modern MUI based IDE system that should make the Amiga developer able to use his favourite Compiler system with a modern looking GUI System with features like filetype handling, Build/Make, TextEd
An AmigaOS/MorphOS MUI custom class which provides application programmers a component to automatically arrange graphical objects in layout (from left to right on several lines) according available space.
An open source IDE for AROS Research Operating System
The open source repository for the Professional File System for Amiga.